From the manual we get this:
This looks good for audio/PTT connection:
Appears to be a full size DIN5 connector. No store cable for that at the time of writing. The homebrew audio cable will look like this:
DIN5 pin 1 (Audio In) → 3.5mm TRRS ring 1 (RIG_AFIN)
DIN5 pin 2 (Gnd) → 3.5mm TRRS sleeve (GND)
DIN5 pin 3 (PTT) → 3.5mm ring2 (RIG_PTT)
DIN5 pin 4 (Audio Out) → 3.5mm TRRS tip (RIG_AFOUT)
That’s a bummer. Looks like industry standard MiniDin6. That would make things easier.
Female DB9 connector on the radio’s side for some reason. 
No pinout info, but we can assume/hope for standard pinout with RS-232 levels.
The homebrew serial cable will look like this:
DB9 Pin 2 (RxD) → 3.5mm TRRS tip (RIG_RXD)
DB9 Pin 3 (TxD) → 3.5mm TRRS ring 1 (RIG_TXD)
DB9 Pin 5 (GND) → 3.5mm TRRS sleeve (GND)
DB9 Pin 7 (RTS) → DB9 Pin 8 (CTS)
Please report your results if you give it a try.
